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drauk
28th Jul 2003, 06:02
How do you pull out circuit breakers in a Cessna? The plane has a mix of circuit breakers, some of which stand proud of the console and some of which are flush. The ones which protude are easy to pull out but this doesn't seem possible with the ones that are flush. What's the trick?

Circuit Basher
28th Jul 2003, 15:09
In my experience, aircraft circuit breakers are not designed for use as switches - they are there to remove power from the circuit in the event of a fault condition that causes that circuit to draw excess current. I know that it is common practice to 'pull' breakers when the equipment on that circuit is known to be faulty or to disable things such as landing gear horns, etc.

Routinely using breakers which are possibly only certified for 1 - 200 cycles as switches will result in the breaker wearing out prematurely and requiring replacement.

If this is a bit of equipment that you regularly wish to isolate, fit a proper switch. If it's a 'one off', then I'm afraid that with a flush breaker, I don't believe there's a way to do it and you're looking at getting a licensed engineer to disconnect the circuit and properly insulate any floating wires.

drauk
28th Jul 2003, 18:16
Thanks CB. I was thinking of an emergency situation rather than as a routine switching operation. I've no wish to disable the stall warner (my examiner did it on my first flight test; I saw him do it but didn't let on). I was thinking more of autopilot malfunction for example.